Solvent‐Free Buchwald–Hartwig (Hetero)arylation of Anilines, Diarylamines, and Dialkylamines Mediated by Expanded‐Ring N‐Heterocyclic Carbene Palladium Complexes

Abstract A highly efficient solvent‐free protocol for the Buchwald–Hartwig (hetero)arylation of anilines, diarylamines, and dialkylamines mediated by the expanded‐ring N‐heterocyclic carbene palladium complex (THP‐Dipp)Pd(cinn)Cl [THP‐Dipp = 1,3‐bis(2,6‐diisopropylphenyl)‐3,4,5,6‐tetrahydropyrimidin‐2‐ylidene; cinn = cinnamyl, 3‐phenylallyl] was developed. The catalytic protocol was efficient for the coupling of amines and (hetero)aryl chlorides and bromides bearing donor, acceptor, and bulky substituents.